Wheels for 03 & 04 shunters?

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SteveO

Guest
I've called Chempix but nobody is in from that department until Monday so can't answer any queries. I'm away on holiday all next week so can't easily chase it up. G&H have been reasonably helpful, but they are also now closed until Monday! I'll wait to see what advice they give.

I'm currently redrawing all the artwork in CAD and will account for all versions of both prototypes in those designs, including sectional resin bonnets too. I'm also currently in negotiations to add to the range, but more of that another time. I think most people realise what the shortfalls of these kits are – I certainly do – but I don't want to add to those oddities either.

To answer your question, Steph, yes it's a whole production run.

Thanks for the insights, advice and sympathies – all very much needed at the moment. At least I have a week in Devon to not think about it!
 

djparkins

Western Thunderer
From your photo it looks like parts are over etched. This could result from being left in the etchant too long but it could also be caused by etching thicker metal or the difference between nickel silver and brass. Varying amounts of etching across the sheet point to production issues, basically lack of control. I am not sure whether Chempix use spray etching, aerated tanks or agitated tanks but everything I have seen produced by them has been extremely consistent, maybe your current etchers aren't quite as well set up to get the most out of older artwork.

You could try having some thinner brass etched to see if it works. Might be time to scan the original artwork and trace it in CAD and then the footplate and louvre issues could be resolved as well. Happy to help with drafting if you need it.

These are good points. The etch factor for NS is significantly greater than for brass. You also need to know what thickness material/type the artwork was drawn for.
 

djparkins

Western Thunderer
As an aside, it is very rare in production terms to be able to shift suppliers for bespoke items. Different manufacturers will have different ways of solving the problems and producing items. It doesn't matter whether we're talking about photo-etched brass sheets, lost wax castings or (my experience) printed circuit boards, motion picture film, audio cables, integrated circuits, etc. etc. If a client starts talking about moving production to alternative sources that's the point at which things start to get 'interesting'*!

They don't get our business unless we can move the work. we've done it before three times. Its a way of keeping down prices! That is why we get all our photo tool work done completely outside/independant of the etching businesses - we own the films then and just loan them to the etching company to do the work.
 

Steph Dale

Western Thunderer
Yep, but I'd put money on you developing your artwork so you know you can move it easily and allow for different manufacturers. That's a very different case to designing with experience of only one manufacturer and assuming/expecting you can move your production to another supplier.

Steph
 

alcazar

Guest
I have to say, the whole thing is very exciting to me.

I find it incredible that DJH produced this as a r-t-r, then a kit and now both, yet DIDN'T ask Slaters to produce the correct wheels. I have one to build and it WILL get the correct ones, as will the two MMP ones I have.

I wonder if they would be open to doing the correct wheels for the Ruston DE165 0-6-0, (PWM651-4), now produced in kit form by Mercian, and the smaller ones needed for when (if) Mike Edge ever releases their early version of that loco (PWM650) in 7mm?

Who/how would I need to ask?

Those locos are pure WR too..........
 
S

SteveO

Guest
David White is your man, Jeff. An absolute pleasure to work with.

I have a couple DJH 03 kits to build too at some point. I talked to Adrian briefly at Reading but it doesn't seem like he'll be re-releasing the 03 and 04 kits he has any time soon. DJH always seem to be out of production of their 03 so for the time being mine are the only realistic proposition of getting one - certainly an 04.

Anyway, holiday fever is starting to build. Better get the suitcases down from the loft.
 

djparkins

Western Thunderer
Yep, but I'd put money on you developing your artwork so you know you can move it easily and allow for different manufacturers. That's a very different case to designing with experience of only one manufacturer and assuming/expecting you can move your production to another supplier.

Steph

But that is the point - I do not - I just follow the same rules. I've never really noticed any major differences between any of the suppliers other than the surface colour and [sometimes] hardness of the metal. Most will alter their suppliers of metal to keep their own costs as low as possible - just as we reserve the right to move etchers for the same reason - it is the way the world is in 2014.

However, the standard of etching is usually pretty much the same in my [albeit limited] experience. We have over 800 photo tools in production [the earliest currently used were hand drawn x8 actual size and go back to 1993] - all would etch fine with any of the suppliers I'm sure and were not created with any partucular supplier in mind.
 

flexible_coupling

Western Thunderer
Right shame to have this kind of setback.... sometimes it seems with some projects that you start out with a bundle of known parts, then you replace 9 of the 10 bits with better things.... and right at the end, something happens to make you just end up replacing that tenth bit - and you've ended up with a brand new production! Like the metaphorical hammer of five handles and three heads.....
 

oldravendale

Western Thunderer
However, the standard of etching is usually pretty much the same in my [albeit limited] experience. We have over 800 photo tools in production [the earliest currently used were hand drawn x8 actual size and go back to 1993] - all would etch fine with any of the suppliers I'm sure and were not created with any partucular supplier in mind.



Would Steve's best option not be to get a test etch made by Chempix? This could then act as evidence to G & H that the phototools are perfectly capable of producing good results? In fact, Steve, if you've had production quantities of etches made was there not an initial OK test etch? Having never commissioned any etches I don't know what the industry protocols are but some evidence that the tool will produce good etches should surely be overwhelming. In these circumstances any production run could and should be rejected.

Interesting to me, David, after many years in manufacturing, that you can move tools around and achieve identical results without tests. It was standard practice for clients to test if they moved product and there were circumstances under which we'd refuse to accept work which had been set up with another manufacturer. Having said all this my business was miles from photo etching (well, with the exception of the "photo" bit:))) and even though retired I'm admittedly a bit very anal in my interest in manufacturing techniques.

Brian
 

djparkins

Western Thunderer
David, after many years in manufacturing, that you can move tools around and achieve identical results without tests.

Brian - that is not quite what I said. What I said was "all would etch fine with any of the suppliers I'm sure and were not created with any partucular supplier in mind". There might well be differences that only I as the designer would detect but they would all be within the acceptable standard for sale. If an etcher cannot etch a sheet I have prepared then, to me, it would normally be their fault not mine, as all are prepared within the standard etching parameters that they give. The films are not set up with any particular manufactuer.

In my book, if you stay within the parameters it is down to the etcher. If you break the rules it is down to you - see next paragraph! It is this that makes me think that the artwork/tooling is the problem on Steve's 04 etchings rather than any fault with G & H - but it wlll be interesting to hear what Steve reports back to us - as hopefully he will.

On our very thin .006" brass or NS sheets, for 72nd scale aircraft or vehicle parts for example, I will use detail lines as thin as .05mm [whereas the etcher will only guarantee .1mm lines]. So - in these situations I am breaking the rules and so if these lines do not always come out that is my risk and not the fault of the etcher [e. g. detail on a lamp cover less than 2mm in diameter]. Sometimes with these sort of items you will get 100+ frets on a sheet and so you just have to accept a certain percentage of rejects and build it into costings - finer detail for the customer but at a price!
 

oldravendale

Western Thunderer
Brian - that is not quite what I said.

Many apologies David. I misinterpreted what you said - or probably didn't read it properly. Your description of the process is most interesting to me - not that you are ever likely to see me in competition with you!

I remain indebted to you and others who produce kits for us. It is troubling to read stories like Steve's and my comments were made in an effort to propose at least the start of a process which may be of some assistance.

Best regards.

Brian
 

Colin M

Western Thunderer
Steve,

It's nothing you've done differently. That's exactley the same as how the etches came supplied in my 'right price' kit.

(I considered it a reasonable trade off against the low price that some allowance had to be made for much fettling and remaking of a few parts).

Colin
 

mickoo

Western Thunderer
On our very thin .006" brass or NS sheets, for 72nd scale aircraft or vehicle parts for example, I will use detail lines as thin as .05mm [whereas the etcher will only guarantee .1mm lines]. So - in these situations I am breaking the rules and so if these lines do not always come out that is my risk and not the fault of the etcher [e. g. detail on a lamp cover less than 2mm in diameter]. Sometimes with these sort of items you will get 100+ frets on a sheet and so you just have to accept a certain percentage of rejects and build it into costings - finer detail for the customer but at a price!

I did the same with PPD with the EMD spartan cab, the battery box covers have a lozenge grid on top, the material I chose was 0.25mm NS, PPD ask for a 1.2x tolerance of the material thickness therefore minimal size should be 0.3mm wide.

At true scale the lozenges are 0.05mm wide at the tapered end and on the enlarged they are 0.15mm, both really too small to etch in 0.25mm; the true scale even more so! PPD advised me on the phone and by writing that it was outside of their tolerances and I had to write and tell them to proceed, in the end they came out fine, PPD were also very happy too, but could and would not guarantee that outcome all the time. The stirrup latches were also below their tolerances but came out fine.
Image1.jpg
 

mickoo

Western Thunderer
This shot shows two of the problems I'm facing – there are a few more. The corner of the footplate has fallen away, as have the tops of the balance weights on the jack shaft crank.

View attachment 32393

They are having a look at it right now...

I think it's been over etched, if you look at the tabs you can see it has begun to etch into the surrounding material, you can expect some of this but not that much.
Image5.jpg

It might be on the original art work, if so then it needs cleaning up.

Here's a sample from PPD in 0.25mm NS note the crisp half edge tab edges with no overspill onto the part or supporting material.
Image4.jpg
 
S

SteveO

Guest
Steve,

It's nothing you've done differently. That's exactley the same as how the etches came supplied in my 'right price' kit.

(I considered it a reasonable trade off against the low price that some allowance had to be made for much fettling and remaking of a few parts).

Colin
Steve,

It's nothing you've done differently. That's exactley the same as how the etches came supplied in my 'right price' kit.

(I considered it a reasonable trade off against the low price that some allowance had to be made for much fettling and remaking of a few parts).

Colin
Colin, just picking up on this and very interesting. Do you have pics of your kit or have you built it already?

I did once own the 04 kit but it seemed to be OK. I've since sold it so can't make a direct comparison.
 

Steph Dale

Western Thunderer
Steve,
I agree it's interesting, but that way both hell and poor reputations are found.
I wonder if it's time to consider drafting replacement parts for those which aren't working currently. At least you then won't be losing the value of your current etches.
Just a thought.

all would etch fine with any of the suppliers I'm sure and were not created with any partucular supplier in mind.
I think we're arguing the same point, as you've just articulated the issue I was driving at!

Steph
 

Colin M

Western Thunderer
I started the kit, but I think the balance weights are still on the etch. I've folded the footplate, but I suspect you can still clearly see the variation in the steps. I'll dig it out over the next day or two and take some photos.
 

Colin M

Western Thunderer
Sorry for the delay ...took me a wile to find it. :confused:

More of the kit had been assembled than I recalled, and most N/S parts removed from the frets, so difficult to see the discrepancies in the footplate etc. but I think you see from the parts still attached that the etching does appear exactly the same.

047e.jpg

042e.jpg

044e.jpg

045e.jpg
Colin.
 
S

SteveO

Guest
Thanks Colin, much appreciated.

The quality of the hand-drawn artwork is not the best, but I can definitely see your sheets have been under-etched compared to mine – there is a difference in the brake block panels, where mine have been etched away slightly, particularly around where the rod attaches. Luckily, these were redone as a separate unit and resupplied. The footplate artwork is also being redone, so hopefully I'll be able to ship these out shortly.

You're making a good job of yours so far, so keep it up!
 
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